The Center for Investivagative Reporting - This story was edited by Rob ert Salladay and copy edited by Nikki Frick and Christine Lee

On a residential street in San Diego County, Calif., Chula Vista police had just arrested a young woman, still in her pajamas, for possession of narcotics. Before taking her away, Officer Rob Halverson paused in the front yard, held a Samsung Galaxy tablet up to the woman’s face and snapped a photo.

Halverson fiddled with the tablet with his index finger a few times, and - without needeing to ask the woman's name or check her identification - her mug shot from a previous arrest, address, criminal history and other personaql information appeared on the screen.